Team Sahi
If you are trading in the Indian derivative markets today, the "old" rules no longer apply. As of January 1, 2026, the NSE has fully transitioned to the new lot size regime. Whether you are calculating your margin for a Nifty option trade or adjusting your hedge ratio for Bank Nifty, using the correct lot size is critical to avoiding order rejection or unintended over-exposure.
Below is the current, official lot size table for all major indices, including Nifty, Bank Nifty, and Sensex, effective for the January 2026 expiry and beyond.
| Index | Symbol | Old Lot Size | Current Lot Size (Jan 2026) |
|---|---|---|---|
| Nifty 50 | NIFTY | 75 | 65 |
| Bank Nifty | BANKNIFTY | 35 | 30 |
| Nifty Financial Services | FINNIFTY | 65 | 60 |
| Nifty Mid Select | MIDCPNIFTY | 140 | 120 |
| BSE Sensex | SENSEX | 10* | 20 |
Note:
As of 18 December, traders are in a transition phase:
In simple terms, December expiry is the dividing line between old and new lot structures.
Lot sizes are reviewed periodically to ensure that the notional value of derivative contracts remains manageable as index levels change over time.
This helps:
The revised lots bring down exposure per contract, especially in Bank Nifty and Midcap Nifty, where absolute contract values had grown significantly.
With smaller lot sizes, each contract now represents slightly lower market exposure, which can be helpful for risk-controlled trading.
If you trade fixed quantities (for example, 2–3 lots), your overall exposure and payoff profile will change from January onwards.
Option sellers should reassess:
Even a small lot size reduction can impact payoff symmetry and breakeven levels.
Certain day spread order books will not be available for specific contract combinations around the transition period, which is relevant for traders running calendar or spread strategies
With the change now close at hand, traders should: